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IPIS - Indoor Positioning and Identification System

Thursday, 22 April 2010 10:51 | Written by Administrator |

The term localization means determining an object or people location in space and time.

There are several localization technologies and different techniques used according different needs. The most known localization technology is GPS, and it is used all over the world. GPS is now part of our day life in many and different ways, like navigation systems on our cars, mobile phones, and many other applications.

Joining GPS with another technology that permit the transport of data, like gsm or gprs, allows us to send the information obtained from GPS to somewhere else. This is the concept behind tracking systems.

Nowadays, there are several commercial devices capable of doing that. So, creating a location or tracking system is relatively simple.

GPS Module

GPS works pretty well for navigation and location systems, but only when the device has a line of sight to the satellite constellation, because GPS signal. When indoor, GPS is useless. In this case, we need to adopt a different approach to determine an object position. Zigbee, Bluetooth, RFID, WI-FI and others low-range technologies can be used.

To use low-range technologies to determine position, we need to have a network of fix nodes and mobiles nodes, the ones which position we want to know. The principle of operation is to determine the signal strength of all base station and use this information, and the known locations of the base stations, to estimate the position of the mobile device.

The problem associated with this technology is the accuracy. To achieve a great level of accuracy, a high number of base stations is needed. Even so, that’s not completely truth, because signal can suffer sudden variation in indoor environments, for instance, because of multipath effects. In the other side, the signal strength has a nonlinear relation with the distance.

Try to solve get a better level of accuracy using a small number of base station, our group is focus on development of antennas to be used in indoor environment.

Prototype of a Multi-Patch Antenna

Another objective is that, the know-how obtained from indoor could allow us to use the same technology in outdoor location.

Another part of our investigation, is exploring the capabilities of mobile devices the be integrated in our location system. One of our main goal, is to be able of guide a person inside a building or in an outdoor place, using our base station network, using an mobile device which will be the person eyes.